Arsenic levels in drinking water in eastern Hungary are above EU limits and significantly higher than in either Romania or Slovakia, is the outcome of a report by a group of European researchers published recently. Whereas only 8% of drinking water topped the EU limit of 10 micrograms per litre in the Romanian and Slovakian counties, in eastern Hungary nearly 70% of those monitored were beyond the 10 microgram EU drinking water standard.
Arsenic contamination is not unique to Bangladesh (see a world map on arsenic contamination
). Highly elevated levels of arsenic of natural origin have been reported in groundwater in many parts of the world. Arsenic poisoning due to excessive exposure to natural and anthropogenic arsenic in drinking water has been reported in Argentina, China, Taiwan, Thailand, India, Mexico, USA, Ghana, Hungary, United Kingdom, Chile, New Zealand, and Russia (CSIRO, 1999).
The release of arsenic, a potent human carcinogen, from bedrock into groundwater is a growing public health concern because groundwater is increasingly used as a source of drinking water. It is known that large numbers of people have been exposed to arsenic through water consumption but information about arsenic levels in groundwater in Europe is scarce.
Lately European researchers had a closer look at the situation in Hungary, Romania and Slovakia by using arsenic speciation methodology.
Photo: A typical scene on the Hortobagy Puszta landscape in Eastern Hungary
at the Institute of Environmental Medicine, Stockholm
, and her team measured levels of arsenic metabolites in urine and arsenic concentrations in water to assess exposure levels. For this purpose, 520 individuals from four Hungarian, two Slovakian and two Romanian countries were investigated by measuring inorganic arsenic and methylated arsenic metabolites in urine by high performance liquid chromatography with hydride generation and inductively coupled plasma mass spectrometry. Arsenic in drinking water was determined by atomic absorption spectrometry. They also considered exposure to arsenic from tobacco smoke and foods like rice, potatoes and poultry.
Findings of the study
They found a wide variation in exposure even in areas already known to have raised levels of arsenic in drinking water. Some areas, particularly eastern Hungary, were shown to have drinking water levels that exceeded the European Union drinking water standard. Also a significant correlation was seen between arsenic in water and arsenic in urine (R2= 0.46). Median concentrations were significantly higher in both the water and the urine samples from the Hungarian counties (11 and 15 µg dm–3, respectively; p < 0.001) than from the Slovakian (0.94 and 4.5 µg dm–3, respectively) and Romanian (0.70 and 2.1 µg dm–3, respectively) counties.
Vahter found a wide variation in the pattern of arsenic metabolites in urine among individuals. At low water arsenic concentrations, the relative amount of dimethylarsinic acid (DMA) in urine was increased, indicating exposure via food. Also, high body mass index was associated with higher concentrations of arsenic in urine (p= 0.03), mostly in the form of DMA. Smokers had significantly higher urinary arsenic concentrations than non-smokers (p= 0.03). The researchers hope to explain their findings by looking at the nature of arsenic metabolism. They also plan to compare their results with studies carried out on populations which have had different nutrition and higher exposures to arsenic.
In conclusion, elevated arsenic exposure via drinking water was prevalent in some of the counties. Exposure to arsenic from food, mainly as DMA, and cigarette smoke, mainly as inorganic arsenic, are major determinants of arsenic exposure at very low concentrations of arsenic in drinking water.
A.-L. Lindberg, W. Goessler, E. Gurzau, K. Koppova, P. Rudnai, R. Kumar, T. Fletcher, G. Leonardi, K. Slotova, E. Gheorghiu and M. Vahter, Arsenic exposure in Hungary, Romania and Slovakia
, J. Environ. Monit., 2006, 8, 203
I. Varsányi, Z. Fodre, A. Bartha, Arsenic in drinking water and mortality in the Southern Great Plain, Hungary
, Environ. Geochem. Health, 13 (1991) 14-22. doi: 10.1007/BF01783491
M. Borzsonyi, A. Bereczky, P. Rudnai, M. Csanady, A. Horvath, Epidemiological studies on human subjects exposed to arsenic in drinking water in Southeast Hungary
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